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How would you access I/O ports in protected mode? I've read that you would need a TSS selector setup with and I/O bitmap set to all 1's or something like that.  How would you go about setting this up?
thanx
Matt

You could either do that (you'll need to read the Intel documents about TSS, they're quite lengthy)...or, the easier way, just set IOPL in the EFLAGS of the process to match its CPL.